Air vented tank drain



Feb- 16, i943- M. N. JOHNSON I 42,311,177

' 4 AIR VENTED TANK DRAIN I Filed March 26, 1941 Ely. .1

Patented Feb. 16, 1943 UNITED STATES PATENT OFFICE Am VENTED TANK mmmMelvin N. Johnson, Faribault, Minn. Application March zo, 1941, serialNq. 385,219

(Cl. ass-20s) 3 Claims.

My invention provides an extremely simple and ting such as may bepurchased on the marketor adapted for various uses by plumbers, steamfitters and the like, and wherein the pipe fitting may be easily usedfor the, application of an air vent tube thereto.

Generally stated, the invention consists of the novel devices,combinations of devices, and arrangement; of .parts hereinafterdescribed and defined in 'the claims. In the accompanying drawing whichillustrates the invention, like characters indicate like partsthroughout the several views.

Referring to the drawing:

Fig. 1 is a view -in elevation outlining a. water heating systemincluding a closed pressure tank equipped with my improved air vent tankdrain, some parts being broken away;

Fig. 2 is a view Partly' in side elevation and partly in section andwith some parts broken away showing a four branch pipe fitting and airventing tube incorporated therewith Fig. 3 is a view corresponding toFig. 2 but illustrating the invention applied to a pipe fittingoftheTtype;

Fig. 4 is .a sectional view illustrating a modication of the air closingcap and a portion of a pipe fitting: and

Fig. 5 is a fragmentary elevation of a modified arrangement.

Referring first to the structurev illustrated in Figs. 1 and 2, thenumeral III indicates a hot water heater or boiler as shown having' hotwater outlet pipes II and IIa and return pipes I2. The hermetic-allyclosed pressure -tank I3 is shown as connected by a pipe I6 to one ofthe outlet pipes, to wit, the pipe I I'.

The pipe coupling I5 is shown in Fig. 2 and has an externally threadedneck or nipple I6 and also has three internally threaded necks I1, I8and I9. Either of the necks I8 or I9 at will may be closed by a plug 20.'I'he threads of all four of the branches are shown as tapered and inthis illustration a faucet or valve 2l is adapted to be applied eitherin the branch I8 or I9, in which case the plug 20 would be applied tothe neck or branch to which the faucet isA not applied'.

.A cap 22, which has tapered internal threads,

is adapted to be screwed on to the branch or nipple I8. The drain pipe23, which extends from the bottom of the tank I3, is shown as screwedinto the neck or branch I1.

The air venting pipe 24, which is much smaller than the pipe 23, isextended from the top or upper portion of the tank I3 downward throughthe drain -pipe 23 and is bent and passed through an annular plug 25applied to the interior of the nipple or neck I6. 'Ihis plug 25 can beapplied as shown and stated either by molding a solder or other metalinto the interior of the said neck I6 and uniting the same with afluid-tight joint both with the neck or air venting pipe. Obviously whenthe cap 25 is screwedI tightly on to the tapered threads of the nippleI6, the passage of waterV from the fitting and the passage of air to theair venting tube will be cut off. However, with the tapered threadsI ifthe cap lbe loosened so that there is leakage of air between the taperedthreads, air will pass to the air venting tube 24, but this will notpermit the escape of water until, of course, the faucetis opened,whereupon the water will Ibe free to flow from the tank and air will beadmitted to the tank to replace the outwardly flowing water.

As already indicated, the faucet can be applied at will to either of theinternally threaded necks or branches I8 or-IS.

kIn the structure illustrated in Fig. v3 the T- tting I5a is providedwith an externally threadl ternally threaded nipple Ita is screwed a capo described structure.

22a, and into the neck or branch I8a Ais screwed the threaded end of a.faucet or valve 2Ia. In this structure the drain pipe 423a is screwedinto the branch or neck I'Ia. The air venting pipe 24a,

which is'brought down through the drain pipev 23a, is passed through anannular plug 25a that corresponds to the annular plug 25 of` the rst thecap tothe neck or nipple by means of closely engaging non-taperedthreads; and for such an arrangement I employ a structure such as shownin Fig. 4. In this. structure the neck or nipple In this modied arrange-Ib is provided with an annular plug 25h through which the air receivingend of the vent pipe 2lb is passed as in the previously describedstructures. In this instance, however, the cap 22h is provided with anair vent 26 and with an axial boss or raised at surface 21 which. whenthe cap is screwed tight, Aengages the end of air tube 2lb and closesthe same. With this structure for air venting purposesit is onlynecessary to slightly unscrew the-cap so as to permit air to passbetween the surface 21 and the engaged'inner end of the tube 2lb orbushing 25h or both.

The air vent tank drain described may be very cheaply made and assembledand can make use of pipe iittings such as may be found on the market oreasily obtained. In actual practice the eillciency of the device hasVbeen demonstrated.

In the modified structure illustrated in Fig. 5 the cap 22e, whichcorresponds to the cap 22h, can be left vtightly screwed on to thebodymember. In this arrangement an air valve 28 is connected to theinterior of the cap 22e by a coupling 29. With this arrangement valve 28will be normally closed, but, when opened in the customary well knownway, air will be -admitted to the interior of cap 22e and, hence,through the air vent pipe to the top of the tank.

The tank, assumed to be the pressure tank of a heating system, may takevarious forms and.

in fact, may be a tank used for various diiferent purposes but requiringdraining and admission of air to facilitate the draining action.

What I claim is:

1. A pipe fitting of the kind described provided with at least threebranches, the first of which is internally threaded to receive theexternally threaded end of a drain pipe; the second of which isinternally threaded to receive the threaded shank oi' a faucet; and thethird of which is externally threaded and internally plugged; a capscrew threaded onto the said externally threaded branch; and an airventing tube extended through said first internally threaded branch andthrough the internally plugged end of said third or externally threadedbranch; said cap when applied serving to close the outer end of said airventing tube.

2. The structure defined in claim 1, in which said cap is provided withan air vent and with an axially located internal surface adapted todirectly close the air receiving end of said venting tube.

3. The structure defined in claim l in which said cap is connected tothe co-operating externally threaded branch by tapered threaded theatmosphere when loosened.

MELVIN N. JormsoN.

